scholarly journals Liquid Crystals as an Active Medium: Novel Possibilities in Plasmonics

2015 ◽  
Vol 1 (1) ◽  
Author(s):  
Roberto Caputo ◽  
Giovanna Palermo ◽  
Melissa Infusino ◽  
Luciano De Sio

AbstractThe peculiar properties of Liquid Crystals (LCs) foster new possibilities in plasmonics. The combination of the intrinsic tunability of LCs with the plasmonic properties of metallic nanoparticles (NPs) provides novel and intriguing features of systems commonly identified as active plasmonics. Being LCs, one of the media whose refractive index can be controlled through the application of external stimuli, they represent a convenient host for enabling plasmonic tunability. On the other hand, the localized plasmonic resonance, typical of NPs, can strongly influence and control the behaviour of LCs. In this paper, we overview several systems of NPs combined with LCs arranged in different configurations. The properties of the resulting systems suggest novel, intriguing outcomes in both fundamental and applied research.

2020 ◽  
Vol 62 (8) ◽  
pp. 1260
Author(s):  
С.Е. Савотченко

A model is formulated, in which the patterns of the formation of nonlinear surface waves with a specific field structure are described. It is shown that there are two new types of waves of selected polarization that propagate along the contact of a photorefractive crystal with diffusion nonlinearity and a nonlinear optical medium with switching. Nonlinearity in such a medium is modeled by a stepwise change in the refractive index depending on the field amplitude. The field structure in the obtained surface waves consists of three components in different areas of the contacting media. As a result of the propagation of a localized light beam along the boundary in the border region, a zone of finite width is formed, characterized by a refractive index that differs from the rest of the medium. In the region behind such a domain, the field decreases exponentially with distance from the border region. The field can decrease with or without oscillations In a photorefractive crystal. The dependence of the propagation constant on the optical characteristics of the media and control parameters is obtained in an explicit analytical form.  


1974 ◽  
Vol 8 (1) ◽  
pp. 3-7 ◽  
Author(s):  
Russell Meares ◽  
Thomas Horvath

Mothers and their neonatal babies were studied during breast-feeding and control periods. Those mothers whose attention to external stimuli diminished during feeding, when this was inferred from habituation rate, had babies whose heart rates significantly increased during feeding. On the other hand, mothers who did not show the expected relative inattention to external stimuli during feeding had babies whose heart rate did not significantly increase when they were fed. The possible relevance of these findings to the study of attachment behaviour is considered.


MRS Bulletin ◽  
1991 ◽  
Vol 16 (1) ◽  
pp. 22-28 ◽  
Author(s):  
J. William Doane

The idea of dispersing micron-size birefringent particles in a polymer to selectively scatter light is not new. In the 1930s Land patented a light polarizing material in which small, oriented solid crystallites were suspended in a clear polymer. The polymer material was selected so that its refractive index matched one of the principal refractive indices of the crystallites while the other did not. The resuit was a light polarizer tha t would pass one component of polarized light but scatter the other component out of the beam path.This idea was substantially expanded by the introduction of liquid crystals as the birefringent material. The orientation of the particles (in this case droplets), and hence the refractive index match and the scattering, could be controlled by an electric field. Such a material could be used as a light shutter for either unpolarized or polarized light. In the mid-1970s this basic concept was applied by Hilsum, but having no way to disperse droplets of liquid crystals in a polymer, he did the opposite and put optically isotropic solid particles in the birefringent liquid crystal.Although Hilsum demonstrated the concept, no commercial device was produced, probably because the shutter contrast was limited. Since then several ways have been found to disperse droplets in a polymer: filling the pores of a microfilter; emulsifying the liquid crystal in a water soluble polymer; and using phase separation methods to create a dispersion of droplets in non-aqueous polymer materials.


1979 ◽  
Vol 42 (04) ◽  
pp. 1073-1114 ◽  

SummaryIn collaborative experiments in 199 laboratories, nine commercial thromboplastins, four thromboplastins held by the National Institute for Biological Standards and Control (NIBS & C), London and the British Comparative Thromboplastin were tested on fresh normal and coumarin plasmas, and on three series of freeze-dried plasmas. One of these was made from coumarin plasmas and the other two were prepared from normal plasmas; in each series, one plasma was normal and the other two represented different degrees of coumarin defect.Each thromboplastin was calibrated against NIBS&C rabbit brain 70/178, from the slope of the line joining the origin to the point of intersection of the mean ratios of coumarin/normal prothrombin times when the ratios obtained with the two thromboplastins on the same fresh plasmas were plotted against each other. From previous evidence, the slopes were calculated which would have been obtained against the NIBS&C “research standard” thromboplastin 67/40, and termed the “calibration constant” of each thromboplastin. Values obtained from the freeze-dried coumarin plasmas gave generally similar results to those from fresh plasmas for all thromboplastins, whereas values from the artificial plasmas agreed with those from fresh plasmas only when similar thromboplastins were being compared.Taking into account the slopes of the calibration lines and the variation between laboratories, precision in obtaining a patient’s prothrombin time was similar for all thromboplastins.


TAPPI Journal ◽  
2018 ◽  
Vol 17 (05) ◽  
pp. 295-305
Author(s):  
Wesley Gilbert ◽  
Ivan Trush ◽  
Bruce Allison ◽  
Randy Reimer ◽  
Howard Mason

Normal practice in continuous digester operation is to set the production rate through the chip meter speed. This speed is seldom, if ever, adjusted except to change production, and most of the other digester inputs are ratioed to it. The inherent assumption is that constant chip meter speed equates to constant dry mass flow of chips. This is seldom, if ever, true. As a result, the actual production rate, effective alkali (EA)-to-wood and liquor-to-wood ratios may vary substantially from assumed values. This increases process variability and decreases profits. In this report, a new continuous digester production rate control strategy is developed that addresses this shortcoming. A new noncontacting near infrared–based chip moisture sensor is combined with the existing weightometer signal to estimate the actual dry chip mass feedrate entering the digester. The estimated feedrate is then used to implement a novel feedback control strategy that adjusts the chip meter speed to maintain the dry chip feedrate at the target value. The report details the results of applying the new measurements and control strategy to a dual vessel continuous digester.


2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Tamara Feldman

This paper is a contribution to the growing literature on the role of projective identification in understanding couples' dynamics. Projective identification as a defence is well suited to couples, as intimate partners provide an ideal location to deposit unwanted parts of the self. This paper illustrates how projective identification functions differently depending on the psychological health of the couple. It elucidates how healthier couples use projective identification more as a form of communication, whereas disturbed couples are inclined to employ it to invade and control the other, as captured by Meltzer's concept of "intrusive identification". These different uses of projective identification affect couples' capacities to provide what Bion called "containment". In disturbed couples, partners serve as what Meltzer termed "claustrums" whereby projections are not contained, but imprisoned or entombed in the other. Applying the concept of claustrum helps illuminate common feelings these couples express, such as feeling suffocated, stifled, trapped, held hostage, or feeling as if the relationship is killing them. Finally, this paper presents treatment challenges in working with more disturbed couples.


2019 ◽  
Vol 4 (1) ◽  
pp. 1-19
Author(s):  
Neri Widya Ramailis ◽  
Dede Nopendri

Discourse is a series of sentences that relate and connect one proposition with the other propositions to from a unity. The main function of the news is not to warn, instruct, and make the public stunned, the main function of the news is to inform and then it is upto the public to utilize the news. There are two ways for the news to be useful to the public, the first to effort news as general knowledge and the second to effort the news a tool of social control. E-Ktp corruption cases are one of the biggest corruption cases that occurered in Indonesia. Therefore, many mass media reported heavilly on E-Ktp corruption cases, one of which was the kompas.com. furthermore, to find out how the writer gets the source the writer gets the source of data and information the writer uses the criminology visual method and then analyzes it using criminology newsmaking theory. However, the results of this study illustrate that the aspect highlighted are those of actors suspected of being involved in E-Ktp corruption cases. Where the media only emphasizes one institution, namely the people’s representative council, even though in this case the involved parties are not only the legislature but case the involved parties are not only the legislature but also from various institutions such as the interior ministry, state-owned enterprises, and private entrepreneurs. In the aspect of media projection Kompas.com make the bulk of the news about E- Ktp corruption cases as news headline and a tranding topic.


Author(s):  
Michael Ahmed

This paper re-evaluates the significance of Sir Curtis Seretse, a black character from the 1960s television series Department S (ITV 1969-70) which has largely been ignored. While earlier critical and academic discourse of Department S has primarily centred on the flamboyant Jason King, the importance of Seretse’s character has been overlooked. Seretse, as the head of Department S, is in a position of authority and power over the other (white) characters of the show. Furthermore, he represents a highly educated character that converses on equal terms with Prime Ministers and Presidents, a unique representation of a black character on British television at that time. Seretse’s appearance on prime time television, at a period when black performers in the media were invariably confined to little more than token characters, is therefore worthy of further attention. This paper examines how Seretse represents a different type of black character not previously seen on British television, when compared to the representations of racial problems on other television crime dramas.


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
M Jelenc ◽  
T Albreht

Abstract Background Policy initiatives, proposals and projects often end up proposing solutions and/or measures that are eventually either not or only partially implemented or they are lacking a system, which would consistently evaluate their implementation and/or impact. Good solutions are often not visible enough to the broader professional community and it is important to identify certain outstanding challenges in cancer control and policy. Driven by the need to better use the outputs from projects on cancer policy, European Commission was trying to address two challenges - one was in solving the problems with the implementation and use of the solutions that have already been proposed and the other one in identifying the outstanding challenges in cancer policy. Results We have decided to follow the structure to develop a series of recommendations and examples of good practices at the national level by selected areas. These would be streamlined into a roadmap to support policymakers at the national and EU level in formulating their cancer policies. Three pairs of targeted recommendations have been identified: Cancer prevention, including health promotion, implementation of the European Code Against Cancer and the reshaping and extension of cancer registriesGenomics and immunotherapy in cancerChallenges in cancer care and governance of cancer control Conclusions Multinational collaboration can bring about important consensual solutions, which build on the existing good practices in the countries. This can be combined well with the existing work on specific areas, carried out both internationally and nationally. Consensus building on jointly defined challenges represents a task that appears to be resolved rather pragmatically. Key message It is important that advance in cancer care and control are quickly analysed and that policymakers receive up-to-date recommendations to improve their policies on cancer control.


2021 ◽  
pp. 216747952199237
Author(s):  
Ondřej Trunečka

This study explores how professional athletes perceive sports journalists and the role of the media. They acknowledge that communication with journalists is an essential part of their profession and appreciate the verified information, knowledge, and dutiful preparation. They consider the main role of media as monitorial. In some cases, they cast doubt on journalists’ ability to evaluate athletic performance accurately, and they are also critical of errors in interviews, however they acknowledgethat there are good, and possibly excellent journalists as well.


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